Intro
What happens when a capacitor C1 appears across R1?
Essentially, C1 delays the voltage change at Vn.
Try it first with Cap
OFF (no delay).
They try with Cap ON (with delay).
How does
C1 change the output?
Your Prime Directive
Adjust the output up (Vo+) or down (Vo-) so that Vn EQUALs Vp!
Your World
You have NO direct knowledge of Vo, R1 or R2,
You can OBSERVE Vp and Vn.
You can ADJUST Vo up or down.
External Circuit World
R1 and R2 deliver a portion of Vo to Vn: B = R1/(R1+R2)
This "tricks" op amp into a gain from Vs to Vo: K = 1/B = (R1+R2)/R1
Try it!
With "C1 OFF", hit "Start" and try to achieve the Prime Directive
Move quickly as possible, without overshoot.
Then click "Show Vo" to view the output.
Now click "C1 ON", hit "Start" and attempt the Prime Directive.
What happened - did a delay in the feedback have any effect?
Share your feedback and thoughts!
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